would be represented, as in fig. 3, by a similar rectangle 

 of which the height (representing the growth) would be 

 approximately doubled : in other words the capital would be 

 doubled. The produce removed would, however, remain. 

 very nearly the same ; because although the coupes would 

 be halved their number (one for each year in the exploit- 

 able age) would be doubled. 



It will be seen that the proportion between the produce 

 felled and the capital would remain constant so long as the 

 exploitable age remained unaltered but would vary with 

 every change in this age. 



Thns, snppose the area dealt with in the above example to he 20 acres, divided 

 into 20 oonpes of one acre each, and that the average ar.nual production has been 

 found to amount to 100 cubic feet solid per acre per annum. Felled at the age of 20 



years, the capital on the ground would always be very nearly cubic feet 



or 20,000 cubic feet, while the quantity of material removed at each felling would 

 amount to 1 x 100 X 20 cubic feet=2,000 cubic feet, or to one-tenth or 10 per 

 cent, of the capital. 



Again suppose the age of felling to be raised to 40 years, and that the area 

 has been consequently divided into 40 coupes containing the proper gradation of age- 

 classes, as in fig. No. 3. The capital on the ground, even assuming the average pro- 

 duction to be slightly higher than before, or 120 cubic feet per acre per annum, 



would be approximately =48,000 cubic feet, or more than double what it 



was before ; while the quantity of material felled (a crop 40 years old occupying half 

 an acre) would be ^ x 120 x 40 = 2,400 cubic feet (very little more than before), 

 and would amount to one-twentieth or 5 per cent, of the capital. 



Normal forest. — A forest is said to be normal when, in 

 addition to being constituted of a complete series of growths 

 of all ages from the seedling to the exploitable tree, each 

 age-class occupying equal areas, it is completely stoc ked 

 and the growth is proportionate to the fertility of the soil. 

 It follows that there is nothing absolute in the term. 

 A capital normal under one method of treatment or age of 

 exploitation would be abnormal under any other age or 

 treatment. 



In a normal forest the quantity and quality of the 

 growing stock are sufficient with regard to the age of 

 exploitation. There are no blanks or damaged stems, the 

 age-classes are distributed in the manner required by the 

 method of treatment and are of proper proportion and gra- 

 dation. 



Abnormal forest. — A perfectly normal forest is therefore 

 a purely ideal creation. No such forests actually exist,* 

 although many approach the condition when they have been 



* Some of the Nilgiri Eucalyptut plantations are almost normal. 



